The present invention is directed to an automatic system for the remote-reading of utility meters, and the like, over the switched telephone-network. It is known to remotely-read utility meters, such as water, gas, and electric. There are various methods for achieving such remote-reading, such as by radio waves, CATV, power-transmission line accessing, and utilizing the switched telephone-network. The present invention is directed to an improved remote-reading system employing the switched telephone-system.
Presently-used remote-reading, switched telephone-systems are operated such that each utility requiring the remote-reading is equipped with a dedicated computer system, typically including a P.C., which contains a listing of all of its customers by account number, physical address, and telephone number. The utility's computer system communicates, by modem, with a telephone company's central-office, automated meter-reading system, which is a trunk-access controller (T.A.C.), that automatically routes an inputted telephone number from the utility system to the subscriber-line loop--or tip and ring lines--at the physical customer-site associated with the particular telephone number. The TAC is central office (CO) equipment that provides a means of controlling a CO-switch test-trunk by a remotely-located computer operated by utilities. The TAC receives the meter reading request from the remote computer. and uses the test-trunk to access the customer's telephone line whose meter is to be read. The test-trunk is used to establish access to the customer's exchange line without ringing or interfering with the customer's use of the line. The access-controller will monitor the line before access to determine if the line is in use; if it is, the telephone number will be repositioned to the end of the program. Also, the access-controller will monitor the line during the read sequence to determine if the end user requests dial tone; if the end user does, automatic meter-reading (A.M.R.) service will be terminated, and the end user will receive immediate dial tone. At that customer-site, there is provided an automatic "Meter Interface Unit" (M.I.U.) which, upon actuation by a signal sent thereto by the utility's computer system via the T.A.C., will "read" the current reading of the four dials, for example, of the meter, and will transmit such reading back to the utility's computer system by the switched telephone-network by means of the T.A.C. Each customer-premise is equipped with this Meter Interface Unit (MIU). The MIU is installed on the customer side of the protector or standard network interface (SNI), and is considered customer-premises equipment (CPE). The MIU is a compact communications device that is connected as a non-ringing extension on the customer's existing phone line. Typically, the MIU can read up to four meters and transmit the data over the exchange line. The MIU can be wired in tandem (up to four) to read 16 meters over one POTS line. At the request of the utility, the access controller sends a "wake-up" tone to the MIU using the test trunk of the CO switch. The MIU "wakes up", reads the ports associated with the meters, and sends the meter-reading data, with other identifying status data, transparently through the access controller to the utility. A meter-encoder is a device that is owned, installed and maintained by the utility. The meter-encoder is attached to electric, gas and water meters; it can be factory or field installed. The encoder remains dormant until activated by the MIU. When activated, the encoder takes a live read, and passes it to the data-collection center. An example of such a system is set forth and explained in depth in the publication entitled "Ameritech Automatic Meter Reading Services Interface Specifications", published by Ameritech Services, Inc., of Arlington Heights, Ill., which is incorporated by reference herein. This publication clearly sets forth the operations, protocol, and the format and control messages of the access and command messages between the utility's computer system and the telephone company's trunk-access controller, as well as between the utility's computer system and the information routed to it from each meter-interface unit at each customer-premise via the trunk-access controller. The AMR software loaded in the utility company's computer receives the data, checks the validity and enters it in the data base for that particular customer. The reading process from the time the TAC receives the customer's telephone number until the data is returned to the utility's computer is approximately 8 to 12 seconds.
AMR service requires a meter equipped with an encoder and an MIU connected to the telephone line via RJII modular jack or the Standard Network Interface (SNI). The existing telephone circuit will provide line-power for the encoder plus provide access for the utility to read the meter.
A typical read-sequence is as follows:
1. Utility programs the utility computer to read 1,000 meters at midnight;
2. The utility computer calls the access controller at the telephone company's central office;
3. The access controller answers and receives a password from the utility computer and disconnects;
4. The access controller calls the computer at a programmed number (security);
5. The computer identifies the first number to be read; the access controller accesses the test-trunk and passes the number to be read;
6. The test-trunk verifies that the POTS is not being used, then accesses the line;
7. A tone is sent from the access controller to "wake up" the MIU;
8. The MIU accesses four ports and four readings are made; the data is distributed to the data collection center;
9. The next number is then read.
Local telephone companies and long distance carriers maintain one or more computer data-base systems which contain current information pertaining to their customers. These database systems are used to support directory-assistance services, emergency-telephone services (911), customer billing, internal-line assignment and maintenance services, etc. The information contained in these data-base systems can include the address at which telephone service is furnished, and the current, switched-network telephone number or numbers that are assigned to, and operational at, the service-address. By enabling access to, and searches of, these data bases by address, the present invention relieves the vendors of other telephone-based services, such as automatic meter-reading, energy-management, telemarketing, and the like, from the burden, cost, delay, and inaccuracies associated with maintaining separate. proprietary data bases for customer telephone numbers. Automatic Meter Reading (AMR) allows a utility to electronically enter an end user's premises to retrieve The current consumption data, without disturbing the end user. The utility can access the telephone-company's central office for interrogation of the end user's utility meters; this action is completed without ringing the phone.